The invention relates to a tiltable arc furnace, with a furnace shell located on a supporting construction and with a cover, the furnace being supported via a platform on rolling-contact cradles and the furnace shell being movable at least substantially at right angles to the tilting direction.
To feed an arc furnace with solid charging material, its shell must be made accessible. To achieve this purpose, it is unimportant for the charging operation whether the furnace cover including the furnace superstructure is removed from the furnace shell, which remains stationary, or whether the furnace shell is moved out of its original position away from the region of the cover. A very commonly used method is to pivot the furnace cover including the furnace superstructure away to the side. For this purpose, the cover-lifting and pivoting mechanism is designed as a revolving tower. Since the center of gravity of the furnace shifts when the cover is pivoted out, tilting moments which necessitate constructions of relatively large dimensions are exerted on the cradles of the furnace. Furthermore, the pivoting mechanism has to be locked for safety reasons.
The additional expenditure on the construction of the cover-pivoting device can be avoided by moving the shell out of the region of the cover.
If the shell is displaced in the tilting direction, high tilting moments again arise. The tilting moments can assume such high values, especially in the case of relatively large furnaces, that considerable outlay in terms of construction would be necessary to overcome them.
If, on the other hand, the shell is moved transversely to the tilting direction, the center of gravity of the shell shifts along the cradle axis, and the tilting moment remains low and can be overcome.
In the off-print "Evolution des Fours a arc type Heroult a chargement rapide" ["The development of Heroult-type rapid-charge arc furnaces"] by Brown, Bouveri & Cie., Baden, Switzerland, from "La Technique Moderne" of 15.3.1939, a furnace of the type mentioned above is described and illustrated. According to FIG. 6, of this publication, a roller-mounted furnace shell of an arc furnace is moved onto a concrete foundation from a platform provided with rolling-contact cradles, by means of a hydraulic device.
In this type of movement, however, the levels of the rail lines of the foundation and platform must coincide exactly. Because of different thermal expansions and effects of wear, especially at the rail joints, in the case of contamination by residual slag and/or splashes of iron, a smooth transition of the rail line from the foundation to the platform is often not guaranteed, so that jarring of the moving furnace shell is unavoidable. This can result in damage to the shell and to its refractory lining. Moreover, an expensive blocking or stopping system is necessary to prevent lateral displacement at the rail joints.